1. Technical Field of the Invention
The present invention relates to information collection and reporting operations and, in particular, to the collecting and reporting of information concerning mobile assets.
2. Description of Related Art
Global positioning system (GPS) receivers associated with mobile platforms (such as automobiles or airplanes) are often used to obtain position information. The process such receivers use to make position determinations from satellite signal measurements is well known to those skilled in the art. Following collection in this manner, the position information is processed in connection with stored geographic map data to visually display on a map the location of the mobile platform.
It is also known in the art for the mobile platform to communicate a piece of collected position information over a wireless communications link to a central processing facility. At this facility, the communicated position information is processed and a visual display is created showing the mobile platform position in association with a geographic map. Remote access to that geographic map containing mobile platform position information may further be obtained by an interested party by remotely accessing the central processing facility over a data network (like the Internet) using a conventional web browser.
It is further known in the art for the mobile platform to communicate a collected piece of position information over a wireless communications link to a central processing facility. At this facility, the communicated position information is processed and a geographic map including an indication of, mobile platform position is created. The geographic map may then be communicated back over the wireless communications link for presentation and display within the mobile platform itself.
A GPS receiver system located on a mobile platform collects position related information. This position information, along with operational information collected by platform sensors, is stored in a database on the mobile platform. The collected and stored information is then periodically transmitted over a wireless communications link to a remote location for further processing and handling. The position and operational information is periodically collected at a first rate and thereafter remotely reported over the wireless communications link at a second rate. Preferably, the first rate is greater than the second rate by a positive integer multiple that is greater than one such that plural time instant collected information is reported in a single communication. Furthermore, the actual time instant for remote transmission is determined when a randomly or pseudo randomly selected offset time period expires as measured following each occurrence of the second rate.
More specifically, the GPS receiver system generates a clock signal and the first and second rates for controlling information collection and transmission, respectively, are measured using a modulo processing operation as applied against the GPS clock signal. In this configuration, the first rate comprises an X time period and the second rate comprises a Y time period, with the expiration of the first and second rate determined by counting modulo X and Y, respectively.
At the remote location, a central controller receives the mobile platform reported information for processing in accordance with tracking management applications. An interface to the central controller allows a user to control the information collection and reporting operations of the control processor (in the mobile platform) as well as the tracking management functions performed by the central controller.